1. Field of the Invention
The present invention relates to an image processing apparatus, which includes a pyroelectric sensor, and a control method.
2. Description of the Related Art
Conventionally, a technique for automatically turning off a power source of an image processing apparatus or transitioning to a power saving state when the image processing apparatus is not used, so as to reduce power consumption, is known. For example, by using a timer, when a predetermined time period has elapsed in a state in which the apparatus does not perform any operation, and a state in which an operator does not make any setting operation or the like, the apparatus transitions to a power saving state. Also, a technique for detecting the existence of a user, transitioning an image processing apparatus from a power saving state to a normal operation state when the user comes close to the apparatus, and transitioning the apparatus from the normal operation state to the power saving state when the user moves away from the apparatus is known (Japanese Patent Laid-Open No. 2012-58645).
As a human body detection sensor disclosed in Japanese Patent Laid-Open No. 2012-58645, a pyroelectric sensor may be used. The pyroelectric sensor has a characteristic in that it ceases to be in a detection state if a detected heat source does not make a large motion even when the heat source exists there. As a result, when the pyroelectric sensor ceases to detect a heat source, the image processing apparatus determines that the operator (user) has disappeared, and transitions to the power saving state.
However, in practice, the operator may be troubled over a setting method of an operation unit in front of the image processing apparatus, or may be in front of the image processing apparatus without any large motion so as to select, for example, copy documents. Even in such case, since the heat source does not make any large motion, the pyroelectric sensor ceases to be in a detection state, and the image processing apparatus transitions to the power saving mode. As a result, when the operator wants to make settings on the operation unit or wants to copy documents after selection of the copy documents is complete, the image processing apparatus transitions to the power saving mode, and the operator has to make an operation for resuming the image processing apparatus to the normal operation state. Then, the operator has to wait in front of the image processing apparatus until the image processing apparatus is resumed from the power saving mode to the normal operation mode, thus considerably impairing the convenience.